Viruses, worms, and other malware continue to create problems for users of computing devices. Various systems and devices may utilize anti-virus software to protect against infection by identifying and removing viruses. However, many viruses may thwart this protection by modifying files in a host operating system (“host OS”) to prevent detection by the anti-virus software. For example, a virus may infect a boot manager for the host OS. The virus, either by itself or through the infected boot manager, may modify other host OS files that are utilized during detection of viruses. If the virus modifies the host OS files to intercept requests that are used by anti-virus software, the virus may then modify these requests and thus prevent the detection.